Whats the advantage of 3480x2160 over 1920x1080 15.6"

Thanks everyone.   This is just what I was looking for. Very good information.  I'll stick with the 1920x1080 15".  Then I also don't have to worry about my other editing programs like HDR, etc working with it.

Many thanks again... This is a great place to get real world answers.  :-)

FWIW I bought a new monitor a couple of months ago, and debated with myself for weeks between 24 inch at 3840x2160, and 27 inch at 2560x1440. Price was not a consideration.

In the end I decided to cut through and just ask myself what I really needed to get my work done efficiently. And then it became a lot easier. I got the 27 inch and haven't regretted it a second.

If you work with text a lot, the sharper text can be nicer to read. But a UHD/Retina/HiDPI/4K display isn't necessarily better for image editing. I switch back and forth between a HiDPI laptop screen and an older 27" desktop display (2560 x 1440), and the higher screen resolution of the laptop doesn't change the image editing experience all that much for me. Except for a few things that look more like disadvantages:

• When you set Photoshop to 100% magnification, on the 3840 x 2160 (4K) display the image will appear at half the height and width of the 1920 x 1080 (2K) display, because the screen pixels are half as tall and wide.
• On a screen with smaller pixels, some controls may be harder to see and grab, like path handles. Photoshop recently added path options that let you change the thickness and color of these so that you can see them better on a HiDPI display.
• If you frequently use Lightroom and Adobe Camera Raw, you may see slower raw editing performance on a HiDPI display because there are four times as many screen pixels to update with every edit. A 1920 x 1080 display has over 2 million pixels to update, but a 3840 x 2160 screen has to constantly recalculate over 8 million pixels. You would have to compensate by also upgrading the CPU and graphics hardware.

If you want to improve the image editing experience on a laptop, choosing a wide gamut display option (if available) would make more difference than higher resolution.

https://forums.adobe.com/people/D+Fosse  wrote Images displayed in web browsers is a special case. Web content needs to be usable on both HD and UHD screens. The only practical solution, and the one currently used by all web browsers, is to scale up when a UHD screen is detected. This effectively turns your expensive UHD screen into an ordinary HD one.

Scaling up an image is one solution. Some web sites are coded to be HiDPI-friendly, so if they detect a HiDPI display, they upload a 2x resolution version of the image instead of just scaling up a 1x image.

MNauman  wrote Whats the advantage of 3480x2160 screens over 1920x1080?

Eye strain. 

If you're considering 3840 x 2160 on a 15-inch laptop screen, it's just way overkill. Don't even think about it. There might be a case with a 24 or 27 inch desktop monitor, though.

You get more screen pixels, double linear resolution and 4x more pixels. It will look smoother and better, up to a point - but there is no practical advantage whatsoever. It will not help you produce better work, and it will not make your work any easier.

Since each screen pixel is individually smaller, 1/4 the physical size, everything displays that much smaller than you're used to. Program interfaces are mostly made for a standard screen density (HD), so without compensation it too will be microscopic (and unreadable) on a high density screen (UHD). The question is if and how the application compensates.

Photoshop does this well now, at least on Windows. But the image itself will be much smaller than what you see now.

Images displayed in web browsers is a special case. Web content needs to be usable on both HD and UHD screens. The only practical solution, and the one currently used by all web browsers, is to scale up when a UHD screen is detected. This effectively turns your expensive UHD screen into an ordinary HD one.